// Copyright (C) 2002-2008 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __I_READ_FILE_H_INCLUDED__
#define __I_READ_FILE_H_INCLUDED__

#include "IReferenceCounted.h"

	//! Interface providing read acess to a file.
	class IReadFile : public virtual IReferenceCounted
	{
	public:
		inline s8	ReadS8()	{ s8  val; read(&val, sizeof(s8));	return val; }
		inline s16	ReadS16()	{ s16 val; read(&val, sizeof(s16)); return val; }
		inline s32	ReadS32()	{ s32 val; read(&val, sizeof(s32)); return val; }

		inline u8	ReadU8()	{ u8  val; read(&val, sizeof(u8));	return val; }
		inline u16	ReadU16()	{ u16 val; read(&val, sizeof(u16)); return val; }
		inline u32	ReadU32()	{ u32 val; read(&val, sizeof(u32)); return val; }

		inline f32	ReadF32()	{ f32 val; read(&val, sizeof(f32)); return val; }
		//! Reads an amount of bytes from the file.
		/** \param buffer Pointer to buffer where read bytes are written to.
		\param sizeToRead Amount of bytes to read from the file.
		\return How much bytes were read. */
		virtual s32 read(void* buffer, u32 sizeToRead) = 0;

		//! Changes position in file
		/** \param finalPos Destination position in the file.
		\param relativeMovement If set to true, the position in the file is
		changed relative to current position. Otherwise the position is changed
		from beginning of file.
		\return True if successful, otherwise false. */
		virtual bool seek(long finalPos, bool relativeMovement = false) = 0;

#ifdef SC5_USE_EXTRA_FILE_FUNCTIONS
		//! Get current file descriptor.
		/** \return current file descriptor. */
		virtual int GetFileDescriptor() = 0;
#endif

		//! Get size of file.
		/** \return Size of the file in bytes. */
		virtual long getSize() const = 0;

		//! Get the current position in the file.
		/** \return Current position in the file in bytes. */
		virtual long getPos() const = 0;

		//! Get name of file.
		/** \return File name as zero terminated character string. */
		virtual const c8* getFileName() const = 0;

		virtual void* getBuffer(long* size)  {
			return 0;
		}

		virtual void* getExternalBuffer(const char* filename, long* size) {
			return 0;
		}

		virtual bool isAllInMemory() const
		{
			return false;
		}
	};

	//! Internal function, please do not use.
	IReadFile* createReadFile(const c8* fileName);
	//! Internal function, please do not use.
	IReadFile* createLimitReadFile(const c8* fileName, IReadFile* alreadyOpenedFile, long areaSize);
	//! Internal function, please do not use.
	IReadFile* createMemoryReadFile(void* memory, long size, const c8* fileName, bool deleteMemoryWhenDropped);

#endif

